The climax of Coronation Street's dramatic serial killer storyline attracted an audience of more than 15 million viewers to the ITV1 show.

The soap opera has been running one of its biggest ever stories as murderer Richard Hillman struck again, killing the character of Maxine Peacock, played by Tracy Shaw.

And the popularity of Monday night's double bill led to the National Grid reporting a massive power surge during the soap's commercial breaks.

An estimated 15.3 million viewers watched the first instalment of Coronation Street at 1930 with 15.6 million tuning in at 2030 to watch the murder, according to unofficial overnight figures.

A National Grid spokesman said: "Obviously, there was a huge audience which meant at the end of the programme people were getting up, turning lights on, going to the toilet, opening fridge doors and boiling kettles."

"It's that concentrated period when a
programme finishes and millions of people around the country go and do something else other than watching Coronation Street."

By 1600 GMT on Tuesday, the Independent Television Commission, ITV's watchdog, said it had received 27 complaints from viewers about the episodes.